The present invention relates to a novel applicator for topical anesthetics and a method using said novel applicator which provides for pain-free injections in mucosa by the application of a topical anesthetic followed by an injection limited to penetrate the mucosa only to the extent of penetration of the topical anesthetic.
It is estimated that 50% of dental patients avoid treatment because of the expected pain, especially pain produced by needles and injections. In addition, stress, in the form of pain, reduces a patient""s immunological response. As a result, post-operative recovery times can be extended and the risk of complications increased.
Topical anesthetics are well known in dental applications and are used to anesthetize oral tissues prior to performing certain dental procedures, such as scaling, root planing, polishing, probing, needle injection for nerve blockages, restorative bonding, suture removal, gingival curettage, tissue grafting, application of antibiotic fibers into periodontal pockets, and soft tissue biopsies.
The typical technique for application of the topical anesthetic during dental or oral surgeries involves the use of anesthetic supplied in gel or liquid form. The dentist dips an absorbent swab, made of cotton, foam, polymer or gel matrix, or the like, into the anesthetic and then transfers the anesthetic to the desired location in the patient""s mouth. After the topical has anesthetized the area, a hypodermic syringe is used for delivery of further medications.
There are several drawbacks to the conventional method. First, the depth of penetration of the hypodermic exceeds the limited area of penetration of the topical anesthetic which is in the range of 2-4 mm. As a result, although the topical anesthetic reduces the amount of pain experienced prior to the hypodermic injection, the procedure is still painful due to the deeper, unlimited penetration of the hypodermic syringe. In addition, topical anesthetics are less effective when applied by swab to certain oral mucosa which are keratinized, such as the palate, due to reduced penetration through the keratin layer as compared to other mucosal surfaces. Deeper penetrations of topical anesthetic into keratinized mucosa may also take as long as 2 to 4 hours.
Unlike these other systems, the present invention provides a method that controls the depth of penetration of the hypodermic syringe. The syringe is limited in depth of penetration to the depth of mucosa anesthetized by the application of the topical anesthetic. As a result, the patient experiences greatly reduced pain. This in turn leads to shortened recovery time, reduced complications and increases the likelihood that patients in need of treatment will actually seek treatment. The method also employs a novel applicator designed to increase the penetration of the topical anesthetic into keratinized mucosa.
The present invention is a method and means for accomplishing pain-free injection in mucosa, specifically in dental applications. The method is accomplished by applying a topical anesthetic to the desired mucosal area by means of a novel applicator swab, comprising a handle on which is attached an absorbent material and an abrasive portion. The swab is dipped in topical anesthetic and placed at the desired oral location, where the abrasive portion is used to mildly abrade the oral mucosa. Immediate contact with the topical anesthetic to the slightly abraded area greatly increases the degree of penetration of the topical anesthetic into the oral tissues. The application of the topical is then followed with an injection which penetrates the tissues only to the extent of penetration of the topical anesthetic. Various devices of fixed length may be used which limit the penetration of the injection such as a drastically truncated syringe needle, a sheath fitted to and covering the needle, a needle shield, and a speculum.